Steam-engine



LE GRAND SKINNER.

STEAM ENGINE.

APPLICATION FILED IuNEzs. |919.

Patented May 11, 1920.

3 SHEETS-SHEET l.

/ullll LE GRAND SKINNER.

STEAM ENGINE. yAPPLICATION FILED JvuNEz. 1919.

1,339,630, Patented May 11, 1920.

3 SHEETS-SHEET 2.

Iqveqinn LE GRAND SKINNER.

STEAM ENGINE.

APPucAmloN mewnmi 25. 19191 1,339,630, Patented Mayu, 1920.

3 SHEETS--SHEET 3.

UNITED STATES PATENT OFFICE.

LE `GRAND SKINNER, OF ERIE, PENNSYLVANIA.

STEAM-ENGINE.

Specification of Letters Patent. Patented lway 11, i920.

Application iled .Tune 25, 1919. Serial No. 306,763.

To all whom t may cof/@cera Be it known that I, Ln GRAND SKINNER, a citizen of the United States, residing at Erie, in the county of Erie and State'of Pennsylvania, have invented certain new and useful Improvements in Steam-Engines; and I do hereby declare the following to be a full, clear, and'eXact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon, forming part of this specification. 4

My invention relates to reciprocating steam engines, and has for its object the provision of means for maintaining desirable thermal conditions within the engine cylinder so as to prevent what is termed initial condensation, caused by hot steam coming into contact with a cooler metal surface within the cylinder. This has heretofore been accomplished, in part, by making the cylinder heads hollow and causing the working steam to circulate therethrough on its way to the inlet valves of the engine. In such cases the heads of the cylinder are heated to substantially the same degree as the steam which enters the cylinder behind the piston, but the piston, being mainly in contact with the expanded steam, will not have as high a degree of temperature as the heads, so that upon entry into the cylinder the steam space has the hot head at one end and the cooler piston at the other end thereof, with the result that while there is no condensation at the hot head, there is considerable initial condensation at the piston.

The object of my invention is therefore, to provide means whereby the end walls of an engine piston may be heated bysteam from the working supply and returning it back into the supply of working steam without substantial waste.

I accomplish this by introducing steam at the normal boiler pressure, directly into the piston, and conducting it therefrom to one of the inlet valves of the engine, so that the steam which passes through the piston becomes intermixed withl the steam in the hollow heads, with the result that the temperature of both the hollow heads and piston is raised to substantially the temperature of the'steam admitted into the cylinder by the inlet valves, so that there will be no condensation of incoming steam on the hollow head, or on the hollow piston, thereby preventing a loss of power because of the condensation of the steam.

The features of my invention are hereinafter more fully explained and pointed out, and are illustrated in the accompanying drawings, in which:

Figure l, is a central longitudinal section of a portion of an engine cylinder and piston, embodying my invention.

Fig. 2, is a rear end View thereof.

Fig. 3, is a horizontal section thereof.

Fig. 4, is a transverse vertical section on the line in Fig. 3.

In these drawings A indicates an engine cylinder, having exhaust ports a, at the central part thereof, which are controlled by the piston in the usual manner, and steam inlet ports a', which are controlled by puppet valves (not shown) which seat upon valve seats a2 in the usual manner, and a segmental steam receiving chamber A3 having ports .713 leading into the cylinder head hereinafter described. B indicates a cylinder head having a cavity therein which is in communicationwith the valve chest A through port openings b', and is provided with bridge walls b2 for the purpose of tying the wall or jacket of the head', to the inner wall thereof. The cavity in said cylinder head communicates with the said steam receiving lchamber through the ports b3 as shown in Figs. 3 and 4.

In these drawings the inlet valves (not shown) which control the inlet ports a, are located on the barrel of. theengine cylinder and the valve chest A nclosing said valve communicates through ports b', with the interior of the head B; butthe location of the inlet valve has no relation to the present invention as said valve may be otherwise located, as may be considered most advantageous, without affecting the scope of the present invention.

Wlithin the engine cylinder A there is a hollow piston C to which a piston rod D is secured, in the usual manner; said piston rod D beingprovided with an extension D which projects through the opening in the head B' formed by the hollow cylindrical wallB2 therein a sufficient distance to permit the piston to make its required stroke without drawing the piston rod extension D out of the head B. This piston rod extension D', I make hollow, the interior thereof being of suilicient diameter to Vrevceive a tube E thereinto and leave the eX- terior of said tube E in spaced relation to the interior surface of the hollow piston rod extension D.

The interior of the piston rod extension D is somewhat reduced in diameter at the inner end thereof, and the tube E is secured in said reduced opening by means of screw threads cl, so that the piston rod extension D and tube E will reciprocate in unison with the piston C.

From the interior of the piston rod D-D, a lateral opening d leads into the interior cavity of the piston C and from the space between the interior surface of the piston rod D-D and the tube E, a lateral opening Z2 leads through a short piece of pipe d3, also into thecavity in the piston C. It will be noted that the lateral Y opening d is above the piston rod and adjacent to one end of the internal cavity, and the lateral opening cl2, and tube d3 are below the piston rod and adjacent to the other end of the internal cavity of the piston C.

Secured upon the cylinder head B is a cylindrical chamber F which incloses the piston rod extension D', said chamber F being lpreferably provided with a stuffing boX sleeve F which extends into the cylindrical wall B2, where it engages a steam packing ring F2 to prevent escape of steam around the piston rod extension D. Secured in the outer end ofthe chamber F is a tube G, by means of screw threads g, said tube G projecting into the tube E with a sliding fit, far enough so that the tube E will not bel drawn therefrom by the forward stroke of the piston C. From the chamber F a steam pipe II leads into the steam cavity in the hollow head B while the tube G receives boiler steam through a steam pipe J preferably connected with the steam main K of the engine, above the throttle valve K', as shown in Fig. 2. K2 is a branch pipe in communication with the steam receiving chamber A3 at each end of the cylinder A, and with the throttle valve K through the connection K3, as shown in Fig. 2. I also provide in the steam pipe J a valve J by means of which the flow of steam through the pipe J into the tube G and thence into the piston C can be regulated. For lubricating theV piston rod extension D and tube G I provide an oil cup L which is secured in the top of the chamber F, from which oil may drop upon the piston rod when it extends thereunder during the backward stroke of the piston and upon the tube G during the forward stroke ofthe piston.

In operation the valve J is opened and steam flows into the tube G and thence through the tube E through the lateral opening d into the interior cavity of the piston -C and therefrom through the short tube d3 into the space around the tube E (carrying therewith any water which accumulates in the piston C) and out of the end of the piston rod extension into the chamber F from which it flows into'the hollow cylin der head B and thence through the' port b to the valve chest A intermiXed with steam supplied direct to the hollow cylinder head B from the steam main K and when the throttle valve is opened and steam enters the cylinder between the steam heatedv head B--B and steam heated piston C through the inlet port a, it comes into contact with metal surfaces all of which are of substantially equal thermal conditions with the incoming steam, said surfaces having been acted upon by steam of substantially one thermal quality upon all sides thereof, so that those particles of steam which contact with the inner wall B of the cylinder heads and the end walls of the piston C will not become condensed thereupon, thus decreasing the expansion of the steam after it is admitted into the cylinder through the inlet ports of the engine. The piston C propelled forwardly by the steam within the cylinder draws with it the piston rod eX- tension D', and tube F, which tube slides telescopically on the tube G a distance equal to the piston stroke, so that the tubular passage between tube G and the lateral opening al is never broken. During the operation of the engine steam will flow from the steam main l through the pipe J, telescopic tubes IG and G, piston C tail-rod D and housing and duct F and II into the hollow head B by reason of the fact that within the steam main the pressure is greater than in the head B, because said head is not only farther from the source of supply than the steam main K, but the engine is drawing its ste-am out of the head B. In other words, the nearer to the point of exhaust the lower the pressure: and the course outlined above is in nature a by-pass from a point of high pressure to a point of lower pressure,A

through which the natural flow of steam is assisted somewhat by the telescopic action of the tubes E and G so that when the piston moves forward the lengthening of said tubes permits steam to flow thereinto from the point of high pressure, and on the return movement of the piston the shortening of said telescopic tubes assists in causing the steam to How through the piston and to the point of lower pressure within the head. I am thus enabled to heat by means of steam of substantially equal temperature with the working steam, both the cylinder heads and piston, without waste, and later use as a heating medium, it continues its travel to the intake ports of the engine through Vthe inlet valves. It will be noted when the piston C is heated as above described, heat therefrom is imparted to the inner surface of the cylinder A as it reciprocates over the central portion thereof so that when said surface is uncovered by the piston steam will not condense thereon, thus further aiding in the reduction of initial condensation within the cylinder.

It will be obvious to those skilled in the art, that the location of the intake valves and construction of the cylinder and cylinf der head, as illustrated in the drawings, is immaterial to the scope and operation of the present invention, because mechanism embodying my invention can, with equal facility, be utilized in any of the usual constructions of steam engines. It is also obvious that many modifications may be made in the mechanism herein shown and described, as embodying my invention without departing from the scope of my invention.

Therefore having fully described my invention, and the construction and operation of mechanism for suitably embodying the same, what 1 claim as new and desire to secure by Letters-Patent is:

1. A combination in a steam engine of an engine cylinder having an inlet port at the end thereof, a steam supply passage,'a hollow piston having closed ends, a pair of tubes communicating with the cavity in said piston, means to connect one of said pair of tubes with the-steam supply passage, and means to connect the other of said pai'r of tubes with said inlet port whereby working' steam will -flow to said port through said hollow piston.

2. A combination in a steam engine of an engine cylinder having an inlet port at the end thereof, a steam supply passage, a head on said cylinder, a hollow piston in said cylinder, a hollow tail-rod extending outwardly from said piston through said head, a tube of less diameter than the interior of said tail-rod secured within said tail-rod., said tube and said hollow tail-rod each being in communication with the interior cavity of said piston by means of separate openings in the wall of said tail-rod, means to connect said tail-rod with the steam supply passage, and means to connect the tube within the tail-rod with said inlet port whereby working steam may be circulated through said hollow piston.

3. The combination in a steam engine of a cylinder provided with an inlet 4port at the end thereof, a steam supply passage, a hollow piston having closed ends; a hollow tailrod on said piston communicating with the piston cavity by means of separate spaced openings, a pair of telescopic tubes within said tail-rod communicating with the steam supply passage and with said piston cavity through one of said spaced openings, and communicating means between said tail-rod and the inlet port.

4. The 'combination in a steam engine of a cylinder, an inlet valve chest thereon, a steam supply passage, a hollow head on said cylinder, a hollow piston in said cylinder having both ends thereof closed, a-nd means to conduct steam,l from said passage into said hollow piston, and thence through said hollow head to said inlet valve-chest, substantially as set forth.

5. The combination in a steam engine, of an engine cylinder, an inlet valve-chest thereon, a steam supply passage, a hollow cylinder head thereon in communication with said valve-chest, a hollow piston within said cylinder, a pair of tubes communicating with the cavity in said piston and extending outwardly through said hollow cylinder head, means to connect one of said pair of tubes with said steam supply passage, and means to connect the other of said pair of tubes with the cavity in said cylinder head whereby steam will flow to said valve-chest through said hollow piston and cylinder head, substantially as set forth.

(5. The combination in a steam engine, of an engine cylinder, an inlet valve-chest thereon, a steam supply passage, a hollow head on said cylinder in communication with said valve-chest, a hollow piston in said cylinder, a hollow tail-rod extending rearwardly from said piston through said hollow head, a tube of less diameter than the interior of said tail-rod secured within said hollow tail-rod, said tube and said hollow tail-rod each being in communication with the interior cavity of said piston by means of separate openings in the wall of said tailrod, means to conduct steam from said passage into said tube, and means to conduct steam from said hollow tail-rod into said hollow head, substantially as set forth.

'7. The combination in a steam engine, of an engine cylinder, a hollow head thereon,

an inlet valve-chest and port in communica tion with. said hollow head, a steam supply passage to the engine, a tubular connection from said passage to said hollow piston, and a'tubular connection from said hollow piston to said hollow cylinder head, substantially as set forth.

8. The combination in a steam engine, of an engine cylinder having an inlet port, a valve-chest communicating with said port, a hollow head on said cylinder, a source of steam supply for supplying steamr to said valve-chest and hollow head, a hollow piston within said cylinder, a pair of tubes communicating with the interior of said hollow piston and extending outwardly through said hollow head, means to supply steam to one of said pair of tubes from said source of steam supply, and means to conduct steam from the other of said pair of tubes into said valve-chest, substantially as set forth.

9. The combination in a steam engine, of an engine cylinder having an inlet port at the end thereof, a hollow head on said cylinder, a valve-chest in communication with said inlet port and with said hollow head, a pipe to supply working steam to said valve-chest, a hollow piston within said cylinder, means to conduct a` portion of the working steam from said pipe into said hollow piston, and means to conduct the same from said hollow piston into said cylinder head, substantially as set forth.

l0. The combination in a steam engine, of an engine cylinder having an inlet port at the end thereof, a head on the cylinder, said head having a central opening therethrough, a hollow piston insaid cylinder, a hollow tail-rod secured in said piston and extending outwardly through said opening, and having lateral o enings in the wall thereof into the interior of said hollow piston, a tube secured within said hollow tail-rod in spaced annular relation to the interior wall thereof, a chamber secured on said cylinder head inclosing and communicating with said tailrod, a tube secured in the outer end of said chamber and extending forwardly into the tube secured within said tail-rod, means to conduct a portion of the engine working steam into said tube, and means to conduct steam from said chamber to said inlet port, substantially as described.

l1. The combination in a steam engine, of an engine cylinder having a valve controlled inlet port lat the end thereof, a hollow head thereon in communication with said inlet port, having a central opening therethrough, a hollow piston within said cylinder, a hollow tail-rod secured on said piston having openings in the wall of said tail-rod communicating with the interior of said piston adjacent to the inner surfaces of each end wall thereof, a tube secured within said hollow tail-rod between said openings in the wall thereof, so as to permit the passage of steam 7ithin said tail-rod around said tube, a ring of packing within the central opening in said. cylinder head and around said tail-rod, a stuing boi; sleeve around said tail-rod adapted to press against said packing, a chamber secured to said stuffing-box sleeve and inclosing said tail-rod, a tube secured in the end of said chamber and slidably extending into the tube secured within said tail-rod, means to conduct a portion of the engine workin@ steam into said tube #D YD 7 and means to conduct steam from said chamber into said hollow cylinder head, substantially as set forth.

12. T'he combination of a steam engine cylinder, steam supplypipe and steam chest, a hollow piston in the cylinder, means dependent upon the reciprocation of thepis-` ton to supply steam thereto from theV said the interior of said piston, and means toV exhaust steam from the interior of the pis-W ton to the steam chest, when the pressure in the steam chest is reduced by the opening of the inlet valve port.

le. The combination with a uniflow engine cylinder, of a hollow piston therein, a rod projecting from the piston and adapted to work through the cylinder head, said rod being provided with inlet and outlet passages extending lengthwise and opening through the same end thereof and communicating with the hollow interior of the pistomand means to iiow steam through said piston and passages.

'15. The combination with a uniflow engine cylinder, of a hollow piston in the cylinder provided with a hollow tail rod zoinimin'icating with the interior vof the piston, and forming an outlet passage therefrom, an inlet pipe extending within the hollow of the tail rod and communicating with the interior of the piston, and means to flow steam through said tail rod, piston and pipe.

i6. The combination of asteam engine cylinder having inlet ports at the ends and an exhaust port-at the middle, a piston in the cylinder having a lcontinuous circumferential wall which covers and'protects the adjacent cylinder wall from the end of stroke to the middle exhaust port, and means to flow steam through the piston from the steam supply to the cylinder.

17. The combination with an engine cylinder, of a hollow heated piston, means for reducing the pressure of steam inthe piston, means for supplying steam to said piston in consequence of such reduction of pressure, a steam supply passage which communicates with'the cylinder, andmeans for delivering steam from the piston to said y passage. g v In testimony whereof I aflix my signature.

LE G. SKINNER. 

